Everyone above is correct. There is no trick to it.
What ever monorail line you get into, just ask one of the castmembers if you and/or your family could ride in the front of the monorail.
If you are at the oneway Epcot monorail and no one is already sitting in there or no one has already requested to sit there, then they may put you right on.
If you are on one of the Magic Kingdom, Resort, or Transportation and Ticket Center monorails, you just ask the same thing. Sometimes someone just got on at the Contemporary Resort monorail station and may go past the Polynesian and Grand Floridian to get to the Magic Kingdom.
If you were at the Grand Floridan, you would have to wait for an empty one to arrive.
Usually, you only have to wait for one extra monorail, and other time you can walk right on.
Have a great time.
Ray